Bra Measurement Chart

General Bra Measurement Chart Questions

How accurate are bra measurement charts?

Bra measurement charts are based on standard sizing conventions and provide a reliable starting point for finding your size. However, they're not a perfect guarantee of fit—actual fit can vary by brand, style, fabric, and body shape. Charts assume a "standard" body, but real bodies come in many shapes and proportions. Use the charts to determine a starting size, then try on bras in that size and adjust based on fit. Many people find that their chart-derived size is within one size of their best-fitting bra. For the most accurate result, combine chart lookup with a physical fitting or careful online trial.

Why do different charts show different sizes for the same measurement?

Bra measurement charts vary because sizing conventions differ by country, brand, and era:

• Country: US, UK, EU, FR, and AU sizing systems use different cup letter progressions and band size scales.
• Brand: Some brands use vanity sizing (shifting sizes to flatter customers), while others follow strict standards.
• Era: Sizing conventions have changed over time—vintage bra sizing is not directly comparable to modern sizing.
• Rounding rules: Some charts round band sizes down, others round up, and some use different even-number rules.

When using a chart, check which system it follows and cross-reference with the brand's own size chart if available.

What is the most reliable bra measurement chart?

The most reliable chart is the one provided by the specific brand you're shopping from. Brand-specific charts account for their own sizing nuances, materials, and construction. Second to that, a standard US/UK chart like the ones on this page provides a solid starting point. Avoid relying on single-source charts from unverified websites—prefer charts from established retailers, bra manufacturers, or reputable fitting resources. When in doubt, check multiple sources and look for consensus.

Do I need to measure in inches or centimeters?

It depends on the chart and the brand. US and UK sizing traditionally use inches for band size, while EU, FR, and many international brands use centimeters. If your tape measure only shows one unit, use a conversion table (like the one on this page) to convert. Many modern tape measures show both inches and centimeters, which makes cross-referencing easier. Record your measurements in both units if possible—it will save you time when shopping internationally.

Measurement and Sizing Questions

How do I measure my underbust correctly for chart lookup?

To measure your underbust:

• Stand in front of a mirror to ensure the tape is level all the way around your ribcage.
• Wrap a soft measuring tape snugly around your ribcage, directly under your bust.
• Ensure the tape is parallel to the floor and not twisted.
• Exhale naturally and read the measurement.
• Take the measurement twice to confirm consistency.

Use this measurement with the band size chart to determine your band size.

How do I measure my bust correctly for chart lookup?

To measure your bust:

• Wrap the tape around the fullest part of your bust, usually at nipple level.
• Keep the tape parallel to the floor.
• Ensure the tape is not too tight or too loose; it should lie flat against your skin.
• Stand straight and relax your arms at your sides.
• Take the measurement twice to confirm consistency.

Subtract your underbust measurement from your bust measurement to get the difference, then use the cup size chart.

What if my underbust measurement is an odd number?

Bra band sizes typically come in even numbers. If your underbust measures an odd number (e.g., 31 inches), you have two options:

• Round down to the nearest even number (31 → 30) for a snugger band.
• Round up to the nearest even number (31 → 32) for a looser band.

Most fitting guides recommend rounding down for a more supportive fit, but the right choice depends on your comfort preference and the brand's sizing tendencies. Try both sizes if you're unsure.

How do I use the international conversion chart?

To use the international conversion chart:

• First, determine your US or UK size using the band and cup charts.
• Find your size in the US or UK column of the conversion chart.
• Read across to find the corresponding EU, FR, or AU size.
• Note that conversions are approximate—brands vary. Check the specific brand's size chart when possible.

For example, a US 34C corresponds roughly to a UK 34C, an EU 75C, a FR 90C, and an AU 12C.

Technical Questions

What is the difference between US and UK bra sizes?

US and UK bra sizes are similar but not identical, especially in cup sizes above DD:

• US cup progression: AA, A, B, C, D, DD, DDD, G, H, I, J, K
• UK cup progression: AA, A, B, C, D, DD, E, F, FF, G, GG, H, HH, J
• Band sizes are generally the same in inches.

For example, a US 34DDD corresponds roughly to a UK 34E. A US 34G corresponds roughly to a UK 34F. Conversion charts like the one on this page help bridge these differences.

Why do EU band sizes look so different from US band sizes?

EU band sizes use centimeters for the underbust measurement, while US and UK band sizes use inches. This is why an EU band size (e.g., 75) is much larger than a US band size (e.g., 34)—75 cm is roughly 29.5 inches, but EU sizing adds 10 cm to the underbust measurement as a standard convention. The result is that EU sizes don't directly correspond to the raw centimeter measurement. Use a conversion chart (like the one on this page) rather than trying to convert manually.

What is the difference between DDD, E, and F cups?

The letter progression above D varies by country and sometimes by brand:

• In US sizing, the progression is typically D, DD, DDD, then sometimes G.
• In UK sizing, the progression is D, DD, E, F, FF, G.
• In EU sizing, the progression is D, E, F, G.

This means a US DDD is roughly a UK E and an EU F. Different brands may also skip or add letters—some use DDDD instead of G. When shopping, always check the brand's specific size chart rather than assuming a universal progression.

What is a sister size and how does it appear on a chart?

Sister sizes are alternate bra sizes with the same cup volume but different band sizes. On a chart, they appear as diagonals: moving one step up in band size and one step down in cup size (e.g., 34C → 36B) or one step down in band size and one step up in cup size (e.g., 34C → 32D). Our sister size chart shows these relationships visually. Sister sizes are useful when your exact size is unavailable or the band fit is off—but they're not interchangeable with your original size, as the proportions differ.

Usage and Troubleshooting Questions

My chart size doesn't fit—what should I do?

If the chart-derived size doesn't fit, consider:

• Re-measuring: Double-check your measurements—small errors can shift your size by one band or cup.
• Checking the brand's size chart: Brand-specific charts may differ from standard charts.
• Trying sister sizes: If the band feels off but the cup fits, try a sister size (see our Bra Sister Size Calculator).
• Trying different styles: The same size can fit differently across styles (push-up, full-coverage, demi).
• Consulting a professional fitter: A trained fitter can identify fit issues that charts can't.

Should I use the chart for sports bras, strapless bras, or nursing bras?

Standard bra measurement charts are designed for everyday bras. Specialty bras require different sizing approaches:

• Sports bras: Often need a snugger band for support—see our Sports Bra Size Calculator.
• Strapless bras: Require a significantly snugger band to stay up—see our Strapless Bra Size Calculator.
• Nursing bras: Accommodate size fluctuations and prioritize comfort—see our Nursing Bra Size Calculator.

Use standard charts as a starting point, then adjust for the specialty bra's specific fit requirements.

How often should I re-check my bra size using the charts?

It's a good idea to re-check your bra size every 6–12 months, or after significant body changes such as weight loss/gain, pregnancy, hormonal shifts, or changes in exercise habits. Bras also lose elasticity over time, so even if your measurements haven't changed, you may need a different size if your current bras feel loose or unsupportive. A quick re-measurement and chart lookup takes only a few minutes and can save you from wearing the wrong size.

Can I use these charts for men or non-binary people who wear bras?

Yes. Bra measurement charts are based on body measurements, not gender. Anyone who wears a bra can use the band and cup charts to determine a starting size. However, standard charts are typically calibrated to breast tissue distribution and ribcage shapes more common in women, so people with different body proportions may find that their chart-derived size is less accurate and may need to adjust or try several sizes. The measurement process itself is the same: measure the underbust and bust, calculate the difference, and look up the corresponding size. Use the charts as a starting point and adjust based on actual fit.